1. Field of the Invention
This invention relates to an improved V-belt variable-speed drive and more particularly to the type which enables a sliding sheave to be smoothly shifted in an axial direction of a driving shaft even when the V-belt applies a localized reaction force to the sliding sheave.
2. Description of the Prior Art
With the prior art V-belt variable-speed drive, a hollow cylindrical bearing was provided between a sliding sheave and a driving shaft to shift the sliding sheave in the axial direction of the driving shaft. Consequently, the V-belt applied a localized reaction force to the sliding sheave due to the particular construction of the V-belt variable-speed drive. Both the bearing and sliding sheave were inclined relative to the driving shaft, causing the inner edge of the bearing remote from the stationary sheave to contact the peripheral wall of the driving shaft in an extremely small area, that is, to make an approximately point contact therewith.
Therefore, the conventional variable-speed drive had the drawbacks that the sliding sheave was shifted under varying conditions according to that part of the periphery of the driving shaft against which the inner edge of the bearing abutted, not only considerably reducing the exact responsiveness of the sliding sheave to the rotating speed of the driving shaft, but also leading to the too easy abrasion of the bearing and driving shaft.